Bearings for axially movable parts of textile machines



Aug- 6, 1953 K. LIEBRANDT ETAL 3,099,920

BEARINGS FOR AXIALLY MOVABLE PARTS OF TEXTILE MACHINES Filed April 11, 19Go United States Patent O 3,099,92t BEARNGS EGR AXIALLY MVABLE PARTS F TEXTILE MACEQES Kari Liehrandt, Naiia-herirlingenspom, and Arno Zwingenberger, Marxgrtln, Germany; said Zwingenhei'ger assigner to said llliehrandt Filed Apr. 11, 1%0, Ser. No. 21,278 Claims priority, application Germany May 16, 1959 5 Claims. (ill. 6-86) This invention relates to bearings and in particular to the bearings which support axially movable parts in textile machines wherein rapid axial movement is particularly desirable.

Bearing and guide means for axially movable bars and shafts in textile machines, particularly knitting machines, are frequently a cause of difficulty due to the fact that such parts are conventionally moved in slide bearings. Considerable friction is exerted on such axially movable bars and shafts which should be guided with a high degree of precision although they are frequently more than four meters in length. The forces usually expended in controlling the axial movement of these parts are inordinate.

Furthermore the elements used for control of these parts, such as levers, cams and rolls are subject to excessive wear due to the friction generated by resistance to movement of these large members. In knitting machines this excessive friction due to axially movable bars and shafts severly limits the number of loops formed even when the best possible lubrication means are employed.

ln a chain knitting machine which produces one thousand loops per minute, the axially guided eye needle bars, during laying of the threads across the bearded needles, have to be moved laterally within 0.007 second to the extent of one needle spacing, from a rest position to a maximum accelerated condition and back -to a position of rest. This must be accomplished for exact oscillatory movement between the needles. The friction arising in such slide bearings upon axially movable bars or shafts is therefore a significant obstacle to increasing the operational speed in the manufacture of looped goods.

{[t is accordingly an object of this invention to provide improved bearings for axial movement of shafts in textile machines and in particular to knitting machines.

It is a further object of the invention to provide bearings for textile machines and in particular knitting machines, which assure an increase in the speed of operation of the machines while permitting overall economies in cost.

-lt is a further object of the invention to provide a knitting machine wherein the bearings are constructed so as to provide significant economies in power expended during operation.

lt is yet another object of the invention to provide in a knitting machine or textile machine a bearing arrangement wherein wear upon the members producing axial motion of shafts is signicantly reduced.

lt is still another object of the invention to provide a knitting machine in particular and textiles in general wherein the shafts within a bearing are automatically set to a desired starting position.

it is a still further object of the invention to provide a support assembly for a knitting machine allowing a guide bar to be separated from its supporting shaft, facilitating easy access for the purpose of repairs or adjustments.

In accordance with the invention there are provided in textile machines ball bearings for supporting and guiding machine elements which are moved axially within the bearings. As a further feature of the invention there are provided at both ends of the bearings, springs for axially biasing the shaft with respect to the bearing, which springs ICC cause the sleeves to return to their original position after their displacement. Another feature of the invention resides in the provision of brackets on the guide bar and guiding arms on the supporting shaft, the major releasable connection between these elements being represented by a support shaft between each pair of brackets and guiding arms.

The foregoing and other objects, advantages and characteristics of the present invention will become more fully clear from the following detailed description thereof when read in conjunction with the accompanying drawings.

FIG. 1 shows a knitting machine wherein the features of the invention are embodied;

`FIG. 2 is a section ll-l of FlG. 3 and depicts a detail of FIG. l; and

FIG. 3 is a section Ill-lll of both IFIGS. l and 2, and depicts a detail of PIG. l.

Referring to -FlG. l it will be seen that the arrangement according to one embodiment of the present invention comprises an axially slidable eye needle or guide bar 9 with bearing means, guide means and control elements connected thereto. A guide bar-supporting shaft 1 is rotatably supported by a plurality 0f spaced stationary machine mounted frame bearings 2 and carries a plurality of aligned bar-guiding arms 5 which are clamped thereon and which are capable of making a short tilting movement about the axis of shaft 1. The arms 3 are each provided with ball bearing enclosing barrel sleeves 4 (see FIGS. 2 and 3) in which the axially movable supporting shafts 5 secured to the guide bar 9 are arranged for rolling on a plurality of helically aligned rotatable balls 6, which balls are supported within ball-holding guide sleeves 7 positioned coaxially the barrel sleeves 4. yIt should be noted that the ball bearings formed by the balls 6 and the sleeves 7 cover only half the axial path travelled by the suporting shafts '5 or the guide bar 9 fastened thereto. The supporting shafts 5 are rigidly secured in aligned pairs parallel to the bar 9 upon a plurality of spaced shaft-holding brackets -8 which are rigidly mounted on the guide bar 9 which in turn supports a plurality of thread holders 10.

The supporting shafts 5 represent the major releasable connection between the eye needle or guide bar 9 and the guide-bar supporting shaft 1. The shafts 5 are adapted for sliding withdrawal from within the bar-guiding arms 3 so that the guide bar 9 may be separated, for repairs or adjustments, from the supporting shaft 1, together with all the shaft-holding brackets 8 and the shafts 5.

An expansible biasing spring 11 is connected at one end to an end bracket 3 on the shaft 1 and at its other end to one of the brackets `8 and serves to bias a cam follower roll 14 against a rotating cam 15 by means of a pushrod `12 connected for movement along with the bracket 8, the guide bar 9, and a double arm lever i13 pivotally mounted upon the stationary brace 13. When a motor driven shaft 21 rotates the cam 15 which is keyed to the shaft 21, the bar is made to follow the undulatory variations in the periphery of the cam `15.

FIGURES 2 and 3 illustrates on an enlarged scale one of the guide arms 3 surrounding and carrying each a sleeve 4 which in turn encloses the ball bearing sleeve 7, the balls 6, and the shaft 5, which is shown to be partially bored, positioned on the inside of the bl bearing sleeve 7 for rotation with respect to the ball bearing sleeve and the barrel sleeve 4. It should be noted that although the drawings illustrate the bearing balls 6 as arranged in the helix, any other suitable arrangement of the ball bearings is Within the scope of this invention. -Each sleeve 4 is pressed fitted into its guide arm 3 and is secured against lateral displacement by a pair of annular sleeve retaining springs 16. A pair of sleeve retaining collars 17 are secured into the sleeve 7 by a press fit and have a somewhat larger inner bore than the diameter of shaft but slightly smaller than the inner diameter of the sleeve 7. The collars 17 serve to prevent any disturbance during a possible deflection of the bearing sleeve transverse to the axial direction during the very rapid movement for which the machine is generally designed.

The bearing sleeve 7 and the collars 17 are held in a movable center position on the shaft v5 by two compressible shaft controlling coil springs |18 mounted about the shaft 5 ywhich springs bear on the collars 17 on one end and on shaft mounted centrally recessed .bearing rings 19 and 20 on the other ends. These springsserve to alway return the sleeve 7 to its initial position after any axial displacement.

The bearing rings 20, at the free ends of the supporting shafts l5, are slightly smaller in diameter than the inner lumen of the barrel sleeves `4 so that the assemblies of shafts 5 can be Withdrawn from the sleeves y4 of arms 3, complete with guide sleeves 7, balls 6 therein, retaining collars 17, coil springs 1-8 as Well as with the ring 20 itself, when the structure is disassembled for repairs or adjustments. It will be understood that the spring 11 will also have to be released from between the respective portions of bar 9 yand shaft 1.

ln a similar manner the remaining bars, rails and shafts can .be moved easily and precisely along the axial direction by means of the hearing balls land the bearing parts. These ball bearings also permit rotational movements so that the bars, rails and shafts are capable of performing an axial-rotational movement in addition to the purely axial motion.

In operation the rotation of the cam 1S induces reciprocal motion on the part of the follower 14, the lever 13 and the push-rod y12. The resulting reciprocal motion of the guide bar 9 and the thread holders 10 is rendered comparatively frietionless by means of the ball bearings described. The bar i9 is generally supported upon the stationary shaft 1 from which it depends by means of the guide arms 3 and Vthe ball bearing sleeves 7. When sudi den motion due to the rotation of the cam is imparted to the guide bar 9, the ball bearing sleeves in which the supporting shafts 5 are held vallow shift and effortless motion of the bar.

It should be understood, of course, that the foregoing disclosure relates only to preferred embodiments of the invention that it is intended to cover tall changes and modiiications of the example described which do not constitute departures from the spirit and scope of the invention as set forth in the appended claims.

What is claimed is:

1. In a knitting machine having a supporting shaft journaled for rotational oscillation, a guide bar releasably supported by and substantially parallel to said supporting shaft, a plurality of thread holders attached to said guide bar, the latter being adapted axially to reciprocate with respect to and rotationally to oscillate together 'with said supporting shaft, at least two aligned bar-guiding arms rigidly secured to said supporting shaft, at least one support shaft connected to said guide bar, having a free end traversing said bar-guiding arms and axially reciprocable with respect thereto, the improvement comprising a plurality of rolling members frictionally engaging central portions of said `support shafts, guide sleeves loosely surrounding said central portions of the support shafts within saidguiding arms and having a plurality of apertures, said rolling members being retained in said apertures, and at least rtwo holding brackets, one for operative connection with each of said guiding arms, said brackets being secured to said guide bar, on the one hand, and to a portion of each of said support shafts opposite said free ends and spaced apart from said central portions, on the other hand, whereby relative laxial movement between said guide bar and said guiding arms is assured during the knitting process, in addition to said axial reciprocation with respect to and said rotational oscillation together with said supporting shaft, said support shafts represent-ing releasable connections between said supporting shaft and said guide bar, said support shafts being adapted for slid-ing withdrawal from within said guiding arms, so that said guide bar may be separated from said supporting shaft together with all of said brackets and said support shafts for vrepairs or adjustments.

2. The improvement in a knitting machine as set forth in claim 1, further comprising a barrel sleeve around said central portion of yeach `'of said supportV shafts, rotatably secured to said guiding arms and interposed between said guiding arms and said guide sleeves, said rolling members frictionally engaging both said bar-rel sleeves and said support shafts, so that smooth relative reciprocartion of the moving parts is obtained.

3. The improvement in ya knitting machine as set forth in claim 2, further com rising a pair of bearing rings on each of said support shafts spaced apart from said barrel sleeves, and a ybiasing spring between each of said bearing rings and the ends of said guide sleeves, for holding the latter at a substantially central position with respect to said support shafts, at least the bearing rings at said free ends bieng slightly smaller in diameter than the lumen of said barrel sleeves so as to be passed therethrough when said support shafts are withdrawn from said guiding arms for repairs or adjustments.

4. 'I'he improvement in a knitting machine as set forth in claim 3, further comprising a pair 'of retaining collars loosely surrounding each of said support vshafts and axially interposed between said guide sleeves and each of said biasing springs, said collars providing bearing surfaces for said springs in radial alignment around said support shafts.

5. The improvement in a knitting machine as set forth in claim 4, wherein two support shafts are provided between said bar-guiding arms and said holding brackets, so that rotational movement of said guide bar with respect to said supporting shaft is prevented.

OTHER REFERENCES Samplette Tricot (publication), copyright 1953 by Bearing Produce Company (page 3 relied on), 3333 Lancaster Avenue, Philadelphia 4, Pennsylvania. 

1. IN A KNITTING MACHINE HAVING A SUPPORTING SHAFT JOURNALED FOR ROTATIONAL OSCILLATION, A GUIDE BAR RELEASABLY SUPPORTED BY AND SUBSTANTIALLY PARALLEL TO SAID SUPPORTING SHAFT, A PLURALITY OF THREAD HOLDERS ATTACHED TO SAID GUIDE BAR, THE LATTER BEING ADAPTED AXIALLY TO RECIPROCATE WITH RESPECT TO AND ROTATIONALLY TO OSCILLATE TOGETHER WITH SAID SUPPORTING SHAFT, AT LEAST TWO ALIGNED BAR-GUIDING ARMS RIGIDLY SECURED TO SAID SUPPORTING SHAFT, AT LEAST ONE SUPPORT SHAFT CONNECTED TO SAID GUIDE BAR, HAVING A FREE END TRAVERSING SAID BAR-GUIDING ARMS AND AXIALLY RECIPROCABLE WITH RESPECT THERETO, THE IMPROVEMENT COMPRISING A PLURALITY OF ROLLING MEMBERS FRICTIONALLY ENGAGING CENTRAL PORTIONS OF SAID SUPPORT SHAFTS, GUIDE SLEEVES LOOSELY SURROUNDING SAID CENTRAL PORTIONS OF THE SUPPORT SHAFTS WITHIN SAID GUIDING ARMS AND HAVING A PLURALITY OF APERTURES, SAID ROLLING MEMBERS BEING RETAINED IN SAID APERTURES, AND AT LEAST TWO HOLDING BRACKETS, ONE FOR OPERATIVE CONNECTION WITH EACH OF SAID GUIDING ARMS, SAID BRACKETS BEING SECURED TO SAID GUIDE BAR, ON THE ONE HAND, AND TO A PORTION OF EACH OF SAID SUPPORT SHAFTS OPPOSITE SAID FREE ENDS AND SPACED APART FROM SAID CENTRAL PORTIONS, ON THE OTHER HAND, WHEREBY RELATIVE AXIAL MOVEMENT BETWEEN SAID GUIDE BAR AND SAID GUIDING ARMS IS ASSURED DURING THE KNITTING PROCESS, IN ADDITION TO SAID AXIAL RECIPROCATION WITH RESPECT TO AND SAID ROTATIONAL OSCILLATION TOGETHER WITH SAID SUPPORTING SHAFT, SAID SUPPORT SHAFTS REPRESENTING RELEASABLE CONNECTIONS BETWEEN SAID SUPPORTING SHAFT AND SAID GUIDE BAR, SAID SUPPORT SHAFTS BEING ADAPTED FOR SLIDING WITHDRAWAL FROM WITHIN SAID GUIDING ARMS, SO THAT SAID GUIDE BAR MAY BE SEPARATED FROM SAID SUPPORTING SHAFT TOGETHER WITH ALL OF SAID BRACKETS AND SAID SUPPORT SHAFTS FOR REPAIRS OR ADJUSTMENTS. 